@Override
public Iter iter(final QueryContext qc) throws QueryException {
final Iter ir = exprs[0].iter(qc);
final long len = ir.size();
if (len == 0) throw ONEORMORE.get(info);
if (len > 0) return ir;
return new Iter() {
private boolean first = true;
@Override
public Item next() throws QueryException {
final Item it = ir.next();
if (first) {
if (it == null) throw ONEORMORE.get(info);
first = false;
}
return it;
}
};
}
@Override
public Value value(final QueryContext qc) throws QueryException {
final Value val = qc.value(exprs[0]);
if (val.isEmpty()) throw ONEORMORE.get(info);
return val;
}